PHYS341/2023/Project14

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Introduction: The Conch

Parts of the conch

The conch instrument, also known as a shell trumpet, is a wind instrument that is also home to several types of large sea snails and is highly coveted around the world [1]. The conch shell belongs to the Strombidae family and has a conical structure, with a long spiral shape that tapers at the tip, also known as the spire[2] . Similar to porcelain, the shell has a solid, shiny and translucent exterior and a hollow interior [3]. For centuries, the conch shell has been utilized by several cultures in various ways and continues to be used as a musical instrument today [1].  

In this article, we will be focusing on certain aspects of the conch such as the history, structure, playing technique and the acoustics and spectra of the instrument.

conch shell

History

Triton, demigod and merman, depicted sounding a conch

Researchers have found that the Conch shell is one of the oldest instruments early humans created and used [4]. Depending on the country of origin, the conch instrument has many uses. Throughout history, the shell has been used as a trumpet in ceremonies and rituals. However, due to its powerful and full sound , the most common use of the shell is as a signalling device [5]. The magnitude and intensity the Conch is able to produce is often compared by researchers, in terms of decibels, to an approaching train [6]. In the Mediterranean it is used as a foghorn, in Fiji it may be used to signal fresh fish is available at the market and in Samoa it is used to notify the citizens of curfew [5].  Furthermore, in Greek mythology the Conch is better known as Triton’s trumpet. Triton, a merman and demigod of the sea, was the son of the sea god, Poseidon. One of Triton’s key attributes was the use of the Conch shell to either calm or raise the waves of the ocean [7]. In some religions such as Hinduism and Buddhism, the shell is sacred and used in many rituals [8]. The Conch, better known as the Shanka, was first used in Hinduism by Lord Krishna as a way to signal the start and end of battles. Subsequently, it became known as a sacred object [3]. According to Hindu mythology, the Conch is a sacred symbol of the Hindu god Vishnu (the Preserver) and symbolic of the sacred “Om”sound [3]. It also symbolizes the Dharma, a key concept with different meanings in Hinduism, Buddhism and Jainism [9] . Buddhists believe that the Conch shell symbolizes the doctrine of Buddhism, teachings of Lord Buddha [3].

Structure

The Fibonacci pattern and golden ratio are represented in the structure of the conch cell that is made up of a spiral that extends transversely and longitudinally [10]. The spiral loops around the columella which acts as the central pillar of the conch. When examined closely, the cavity around this central pillar expands in multiple directions, horizontally and vertically. If the dimensions of the transverse and longitudinal cavity are measured, it can be seen that the ratios are relatively proportionate to the golden value [10]. Therefore, the Fibonacci pattern is exhibited by the conch shell. Its unique structure contributes to the resonating frequencies in the cavity that makes the conch the instrument it is [11].

How it's made

Conch shell with side mouth hole

Depending on the context, there are two basic methods the shell is prepared for use. If the spire is shallow, the tip of the spire is cut off to create a mouth hole. This approach is often used in countries such as the Caribbean or the Indo-Pacific region [5].  If the spire is steep, the mouth hole is placed on the side of the spire. This second approach is common in Polynesia and the Pacific and Indian oceans [5]. More often than not, the mouth hole is used on its own. However, in some countries such as Japan, the instrument is played using a mouthpiece placed in the created hole [5].

Japanese conch with mouthpiece

Playing technique

Similar to playing a brass instrument such as a trumpet, a player must first blow into the mouth hole or mouthpiece with vibrating or "buzzing" lips [12]. Depending on how the player utilizes their facial muscles, tongue, teeth, or lip shape, the pitch of the sound the conch produces can be controlled for. In other words, the embouchure plays a significant role in producing different sounds on the conch [2]. A stiffer embouchure would lead to a raise in pitch while a more relaxed embouchure would lead to a drop in pitch. Similarly, a lifted tongue could also lead to a raise in pitch and a lowered tongue would have the reverse effect. Another method of altering the pitch is by placing a hand inside the opening of the conch, also called the aperture [2]. A player may decide to place their hand inside the instrument as a means to lower the pitch.

Acoustics and Spectra

The size and length of the conch determines what pitch it is able to play. As shown in Figure 1 larger and longer shells will produce a lower frequency, whereas smaller and short shells will produce a higher frequency as shown in Figure 2 [8].

The conch shell can be considered both a closed-open system and an open-open system [11]. It is a closed-open system as a player must attach their mouth to one of the open ends (the mouth hole or mouthpiece). A player blowing into the conch shell causes a node at that end which in turns makes it closed. However, the conch shell system can have 1/2, 3/2, 5/2, and 7/2 wavelengths which do not line up with typical closed-open systems. This can only be explained by it being simultaneously an open-open system [11]. Since the lips open and close with sinusoidal vibration, there is sinusoidal pressure variation at the end that is being blown into and the tube opens and closes at the frequency of lip-vibration [11].

Figure 1: Large conch shell with fundamental frequency 251Hz
Figure 2: Small conch shell with fundamental frequency 316Hz

Modern use

Today the conch continues to be used as a signalling device and has even been approved by the United States Coast guard due to its volume [13]. The shell is also a large contributor to the jewelry industry, especially in the Caribbean [14]. It is most frequently jewelry such as bracelets, earrings and necklaces. Furthermore, it is commonly used in jazz music and even in movies such as the Alien to create eerie sound effects [13]. Below is a video of Steve Turre, a famous American trombonist who is known to use multiple conch shells during his jass performances.


References

  1. ↑ 1.0 1.1 http://www.blowtheconch.com/the-conch-tradition.html. Missing or empty |title= (help)
  2. ↑ 2.0 2.1 2.2 Conch Shells as Musical Instruments and in Living Sea Snails. https://spinditty.com/instruments-gear/Conch-Cells-As-Musical-Instruments.
  3. ↑ 3.0 3.1 3.2 3.3 Rhys, Dani. “The Conch Shell or the 'Shankha' – Emanator of Healing Vibrations.” Indian Artwork - Buddha Statues & Hindu Books - Exotic India Art, ExoticIndiaArt, 22 Oct. 2021, https://www.exoticindiaart.com/article/the-conch-shell-or-the-shankha/#:~:text=According%20to%20Hindu%20mythology%2C%20the,is%20the%20god%20of%20sound. https://www.britannica.com/topic/dharma-religious-concept.
  4. ↑ Magazine, Smithsonian. “Hear the Musical Sounds of an 18,000-Year-Old Giant Conch.” Smithsonian.com, Smithsonian Institution, 10 Feb. 2021, https://www.smithsonianmag.com/history/hear-what-18000-year-old-giant-conch-instrument-sounds-180976977/.
  5. ↑ 5.0 5.1 5.2 5.3 5.4 Shell Trumpets- Experimental Musical Instruments, https://www.furious.com/perfect/shells.html.
  6. ↑ Staff, ScienceAlert. “Listen to the Haunting Sound of a Conch Horn Played for the First Time in 17,000 Years.” ScienceAlert, 11 Feb. 2021, https://www.sciencealert.com/earliest-shell-horn-played-for-first-time-in-17-000-years.
  7. ↑ Encyclopædia Britannica. “Triton.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 17 Mar. 2023, https://www.britannica.com/topic/Triton-Greek-mythology.
  8. ↑ 8.0 8.1 Strauchen-Scherer, Bradley. “Brass Beginnings: A Fanfare for the Conch Trumpet.” The Metropolitan Museum of Art, 8 Mar. 2018, https://www.metmuseum.org/blogs/collection-insights/2018/brass-beginnings-conch-trumpet-fanfare#:~:text=Among%20the%20earliest%20surviving%20conch,Oceania%2C%20and%20the%20Americas%2C%20but.
  9. ↑ https://www.exoticindiaart.com/article/the-conch-shell-or-the-shankha/#:~:text=According%20to%20Hindu%20mythology%2C%20the,is%20the%20god%20of%20sound. https://www.britannica.com/topic/dharma-religious-concept.
  10. ↑ 10.0 10.1 Rath, Saroj Kumar, and P. C. Naik. “Fibonacci Structure in Conch Shell.” Current Science, vol. 88, no. 4, 2005, pp. 555–57. JSTOR, http://www.jstor.org/stable/24110253.
  11. ↑ 11.0 11.1 11.2 11.3 Rath, Saroj Kumar, and P. C. Naik. “A Study on Acoustics of Conch Shell.” Current Science, vol. 97, no. 4, 2009, pp. 521–28. JSTOR, http://www.jstor.org/stable/24111880.
  12. ↑ CanDo, and Instructables. “Conch Shell Horn.” Instructables, Instructables, 11 Nov. 2017, https://www.instructables.com/Conch-Shell-Horn/.
  13. ↑ 13.0 13.1 “Conch Facts.” Math, https://www.softschools.com/facts/music_instruments/conch_facts/3043/.
  14. ↑ Dscott. “Caribbean Current - Conch Shells Offer an Earful and Mouthful of Joy.” The Philadelphia Tribune, 28 Feb. 2020, https://www.phillytrib.com/caribbean_currents/caribbean-current---conch-shells-offer-an-earful-and-mouthful-of-joy/article_5a5b8918-689f-5905-9031-171419ef0c1b.html.
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